<a href=showthread.php?s=&postid=7555956#post7555956 target=_blank>Originally posted</a> by JustFin
I have a 75 with a 6 bulb fixture, and right now I'm not using 2 of the bulbs because of overheating plus 6 bulbs is overkill for my tank right now since it is LPS & soft corals- I'm running 2 actinics on the outside, a GE sunlight type bulb, and another that's name escapes me but the spectrum is white like a 10,000K type.
I'm almost certain with the brightness of the 6 bulb you could keep anything light demanding- SPS, clams, anemones, etc. I think the 8 bulb would be too much, plus an 8 bulb fixture would give you even more heat issues than I'm experiencing and make a chiller an absolute must have